Disabilities and Tests
BS 8878 2010 Web Accessibility Code of Practice British Standard " is applicable to all public and private organizations wishing to offer accessible, usable websites to their customers." W3C Web Accessbility initiative has information about How people with disabilities use the Web.
Each disability has at least one relevant test matched to it. The tests are subjective, based on the opinions of the evaluators and the results of the matched tests are only an estimation of how accessible a product is to a person with the disability.
Blind and Severe Visual Impairments
Screen reading for all aspects of computer use may be the main access technology used, and it is important to remember navigational control may be by the keyboard rather than the mouse. Alternative information is required where multimedia, such as images, animation or videos are offered. Links to other areas need to have good labels and make sense when divorced from their web page. Layout, tables and forms also need to remain readable when the framework for the website is removed such as a style sheet. Further advice from WebAim.Tests
Partially Sighted and Visual Acuity
Magnification, the use of high contrast text and alternative background colours may be important to many users with visual impairments. The way contents are laid out and reflow when zoomed also affects ease of reading. Too much clutter on a page can also also cause overlapping of content. Screen-reading may also be used as scrolling horizontally when text is very large can be very tiring. Further advice from UW-Madison with a video on Screen Magnification and the Web.Tests
The ability to change the colour of text and background as well as the text type can be essential for those with visual processing difficulties. Layout, white space and clear navigation links can also help. Blinking, scrolling and other animations are often unhelpful and can cause distractions for some. Further advice from Iansyst Dyslexia and Visual Stress.Tests
Successful use of a web page may depend on colour differences and contrast levels as much as the shape of symbols where colour is used to distinguish items. Size of fonts, their style and the ability to read text against certain background colours is also important and designing in black and white before adding colour can help. Problems may arise where there is no distinction between links and visited links except for the colours. Further advice from Lighthouse International.Tests
For those with dexterity difficulties and strain injuries the mouse and even the keyboard can be difficult to use, along with other input devices, so it is important to have alternative options for navigating around a website. If the features are available via a few select keys on the keyboard it is usually possible to design other input devices to work with these web pages which can help those with severe mobility difficulties. There is also the option of speech recognition which can depend on a good use of headings in the web page design and good layout remains vital for all users with a logical tabbing order. Further advice from WebAIM Motor Disabilities.Tests
Deaf/Hard of Hearing
For those who are deaf, English may not be the primary language; it may be British Sign Language. Readability and text layout are important accessibility factors as are the provision of alternatives for multimedia content with captioning, subtitles and text transcriptions. The use of meaningful graphics and clear headings can also be helpful. Further advice from seehearsurf.Tests
Specific Learning Differences (including Dyslexia)
The option to use a different font, being able to change background colours and plenty of white space with clear navigation are all helpful features. Synthetic speech output for text reading may be a used by some, so the ability to highlight text and send it to the clipboard could be essential for some text-to-speech applications. Being able to zoom text and not lose the shape of the page is also helpful. Further advice from the BDA Dyslexia Style Guide.Tests
Cognitive Learning Disabilities
Clear writing and good use of images and audio can help those with learning disabilities, who may need support for complex use of language. Simple navigation, easy-to-follow links and clear web page design helps everyone, but these features are particularly important for this group of people. Clear feedback when performing actions is beneficial, but too many links and dense text will not help. Further advice from the WebAIM Steppingstones Project on Web Accessibility and Cognitive Disabilities in Education.Tests